This invention relates generally to dishwashers, and, more particularly, to dishwasher system fine filter systems.
Known dishwasher systems include a main pump assembly and a drain pump assembly for circulating and draining wash fluid within a wash chamber located in a cabinet housing. The main pump assembly feeds washing fluid to various spray arm assemblies for generating washing sprays or jets on dishwasher items loaded into one or more dishwasher racks disposed in the wash chamber. Fluid sprayed onto the dishwasher items is collected in a sump located in a lower portion of the wash chamber, and water entering the sump is filtered through one or more coarse filters to remove soil and sediment from the washing fluid. At least some dishwasher systems further include a fine filter system in flow communication with the main pump assembly to remove soil and sediment of a smaller size than those filtered by the coarse filters. The main pump assembly draws wash fluid from the sump to recirculate in the wash chamber, and the coarse and fine filters are used to continuously filter the water in the sump during the re-circulation process.
At least one known fine filter assembly includes a fine filter having a filter screen disposed over a top of a filter body. Soil and sediment is filtered from wash fluid passing through the filter screen, and soil and sediment is collected in the filter body. It is sometimes difficult to remove soil that accumulates in a filter body toward a fine filter drain. The efficiency of the filter is compromised if soil cannot be quickly and completely removed.
In an exemplary embodiment, a fine filter assembly for a dishwasher includes a filter body having a soil accumulation trough. The soil accumulation trough defines a substantially helical flow path between a fine filter inlet and an outlet. A natural flow path is therefore provided to efficiently clean fine the filter assembly with downwardly directed fluid jets generated by a lower spray arm assembly. Soil is directed to a fine filter drain tube with relative ease, thereby facilitating use of more efficient use of a drain pump inlet as a soil collection chamber during wash cycles.
A fine filter screen is disposed over a top of the filter body to filter soil and sediment from fluid flowing through the fine filter assembly, and soil is accumulated in the soil accumulation trough and naturally directed toward the fine filter outlet on the sloped helical path. The soil accumulating trough includes a first end and a second end located substantially adjacent to one another so that the soil accumulation trough extends substantially 360 radial degrees around a circular outer perimeter of the filter body. Thus, a full length of the filter body is used to direct soil and sediment downwardly to the fine filter outlet. An efficient and easily cleaned filter assembly is therefore provided.